A Self-tapping suture anchors are well known in the art. See, for example, U.S. Pat. No. 4,632,100, issued Dec. 30, 1986 to Goble et al., which discloses a cylindrical suture anchor having a drill portion formed at one end and flights of threads formed at the other end. A length of suture is fixedly attached to the suture anchor so as to extend therefrom. The suture anchor may be turned, and hence installed into a target bone, by means of a driver that matingly engages the anchor by means of a splined coupling, with the free end of the suture being stored within the body of the driver. In practice, the drill end of the suture anchor is positioned against the target bone and then the suture anchor is turned by means of the driver. This causes the drill portion of the suture anchor to cut into the bone. As the drill portion of the suture anchor cuts into the bone, thus forming a hole therein, the suture anchor's threads engage the inner surface of the hole. The leading thread flights tap the hole so as to provide a seat for the following thread flights. Once the suture anchor has been seated, the driver is pulled back from the bone, with the stored suture paying out from the interior of the driver.
While suture anchors of the type taught by Goble et al. generally perform well, they are not completely satisfactory for all types of surgical procedures in which suture must be attached to bone. In particular, with the suture anchor of Goble et al., the suture is attached to the anchor by fastening the suture to a disc, which is then fixed in position within a blind hole formed in the proximal end of the anchor. Unfortunately, this arrangement can be cumbersome, particularly where the anchor is to be formed with a relatively small size. Furthermore, with the suture anchor of Goble et al., the splined coupling used to connect the driver to the anchor comprises a polygonally-shaped male portion on the driver and a corresponding polygonally-shaped female portion on the anchor. This construction can present a constraint, particularly where it is desired to form the anchor in a relatively small size. Moreover, when the anchor of Goble et al. is installed in a target bone in the manner taught in the patent, the suture anchor's thread often does not positively engage the cortical layer of that bone. This has sometimes led to less than adequate retention of the suture anchor in the bone, especially where relatively small size anchors have been used.